Ian McKellen as "Toad"

One of the first films I ever saw was Disney's Bambi, shortly after its wartime release in 1942. Perhaps because it made me cry, I've ever since not been much taken with what we then called "cartoons" — at least those which present animals as if they have human attributes, whether Mickey Mouse or, in another style, Babe. Down with anthropomorphicity! That said, of late, the new-style animations are increasingly alluring, from Toy Story to Lion King, despite Simba's having no visible genitalia. In particular, Aardman have broken new ground, since its founders started up in Bristol UK 30 years ago. Their Wallace & Gromit: The Curse of the Were-Rabbit looks and sounds so original that they have won me round to animated movies — and more significantly won an Oscar.

So when Jeffrey Katzenberg called, I said "Yes please" to the chance of working on Aardman's latest joint venture with Dreamworks — Flushed Away. I was to provide the voice for "Toad"; nothing to do with him of Toad Hall but a villainous little pompous beast strutting through the sewers beneath London, where he reigns supreme, did you realise? The story starts with an engaging rat who gets flushed down the loo and lands in Toad's subterranean, watery domain. Toad himself made a similar journey, once his young master HRH Prince Charles dispensed with his amphibian pet. It was a promising project, particularly as I was told the job would take only a few hours in a London sound studio, spread over the year which the animators needed to join together voices and pictures.

Whitey (Bill Nighy), Spike (Andy Serkis) andToad (Ian McKellen)

Eighteen months and many hours of work later, I have only this week in Soho finished, with some relief. Unlike the method used on Magic Roundabout of matching my voice to the already completed images of Zebedee, Peter Lord directed me to record Toad's dialogue in advance of the character's finished appearance onscreen, although helped by showing me some engaging plaster models of Toad. Freed of the restriction of fitting voice to any existing mouth or body movements, I could let fly and soon settled on a fruity voice that might fit the neckless, goitered green-jawed Toad and the imperious stance of the lord of the sewers. As I spoke and spluttered into the microphone, Peter's comments from behind the sound-proof window were always helpful but, line by line, he would never give up until I had belched up a multitude of variations from which he could eventually select the most appropriate.

One disappointment was not to work with the rest of the stellar cast which includes my erstwhile colleagues, Wolverine, Gollum and Detective Fachu from Da Vinci Code. Acting in Flushed Away was a solo business.

I have now seen some of the finished film. There has thus far only been one independent online review, based on a crude version before the Aardman wizardry was complete. The anonymous judgement is not much in favour, proving that it is nigh impossible for a non-professional to anticipate the final effect of an animated movie before it has been finalised. You might as well try and assess a stage play in the rehearsal room or the taste of a meal before it has been cooked. — Ian McKellen, August 2006